1. Field of the Invention
The present invention relates to an apparatus for transfer of a machine part.
2. Description of the Prior Art
Japanese Unexamined Patent Publication Tokkai-Hei 1-284,441 entitled: "Manipulator for a plate bending machine and a robotic device equipped with the manipulator", discloses a method for the replacement of a plurality of fingers (gripper members) of a plate clamping device forming part of a manipulator adapted to handle metal sheets to be processed in a bending press.
Conventionally, the fingers are replaced by means of an auxiliary arm which withdraws fingers of the desired type from a magazine, removes the fingers to be replaced from the plate clamping device, mounts the fingers previously withdrawn from the magazine on the plate clamping device, and deposits the removed fingers in the magazine for subsequent use. These operations are possible because the fingers are secured to the plate clamping device and to associated supports of the magazine by means of a passive snap-engageable securing device comprising a male/female support and guide means, for example, defined by a tang projecting from the fingers and connectable slidably with an associated seat on respective brackets carried by the plate clamping device or by the associated supports of the magazine, and respective locking pins retractable against the action of a resilient means, capable of snap-engaging appropriate holes in the tangs of the fingers to lock them axially onto the brackets.
This automatic system, whilst being highly efficient, requires a rather onerous and highly accurate programming of the control unit, involving complex movements, and further involves the additional cost of the finger displacement/manipulation arm. It is therefore used most advantageously in large or medium scale production in which the higher costs are divided over a large number of products. In smaller scale production it would however be preferable to replace the fingers manually.